1. Field of the Invention
The present invention relates to an electric vehicle having a ground fault detecting system for detecting a ground fault or an insulated state of an ungrounded power supply with respect to a grounded region (ground) of the electric vehicle.
2. Description of the Related Art
Generally, electric vehicles carry a power supply having a high voltage of 200 [V] or higher, for example, which is insulated from the vehicle body as an ungrounded power supply.
A technique has been proposed for detecting a ground fault (including a ground leakage or a lowered insulation resistance value caused by deteriorated insulation) of such a high-voltage ungrounded power supply (see, for example, Japanese Laid-Open Patent Publication No. 08-226950).
According to the technique disclosed in Japanese Laid-Open Patent Publication No. 08-226950, a ground fault of a single ungrounded power supply is determined.
Nowadays, there have been proposed electric vehicles, which have a load energizable by a first ungrounded power supply, such as a fuel cell, and a second ungrounded power supply, such as an electric energy storage, e.g., a battery or the like. However, a ground fault detecting system has not been developed in the art for use on such electric vehicles that carry thereon first and second ungrounded power supplies.